1. Field of the Invention
The present invention relates to a diaphragm chuck with clamping jaws inserted in a chuck body and act on a workpiece to be clamped and are in a driven connection with a diaphragm that is located on a front face of the chuck body, attached to an outer area of the chuck body, and can be deformed by means of a centrally arranged, axially adjustable actuator, with counterweights assigned to clamping jaws located in recesses in the chuck body, and each of the clamping jaws designed as clamping heads being equipped with an offset contact piece that is axially arranged in the direction of the chuck body and runs approximately axially in parallel to the chuck body, the contact pieces being held in recesses worked into the counterweights, and the clamping jaws being clamped against the diaphragm and the counterweights by means of quick-clamping devices that engage in the contact pieces and act in the axial direction of the contact pieces.
2. Description of the Prior Art
A diaphragm chuck of this type is described in DE 199 19 408 B4 and has proven to be effective in practice. In this case, each of the clamping pieces of the clamping jaws is inserted and guided in a jaw carrier that is in a driven connection with the diaphragm, so the jaw carrier thereby follows the adjustment movements of the diaphragm. The clamping jaws of a chuck are ground in for the particular clamping position and for this reason the jaws can only be used with this chuck, assuming the specified precision is to be maintained. Accordingly, exchanging the clamping jaws from one chuck to another is only possible to a limited extent, if at all. Also, supplying new clamping jaws is not a straightforward procedure because they in turn have to be ground in for the chuck on which they are to be used. When a machining operation is modified, in which case the clamping jaws have to be ground out, this takes a lot of time and effort. What is more, the investment costs for stocking a large number of clamping jaws are considerable.
The task of the present invention is therefore to develop the diaphragm chuck of the aforementioned type in such a way that the clamping jaws do not have to be ground out in the clamping position of the chuck, but to enable them to be manufactured separately and machined to the precise dimensions. In this way, it should be possible to achieve a situation in which the clamping jaws are not dependent on a particular chuck, but can easily be exchanged between chucks and new jaws can be supplied for existing chucks, with the effect that the setup times can be significantly reduced and that workpieces can be machined at a favourable cost.